Honing element



Feb. 18, 1958 a. A. SAUNDERS 2,823,498

HONING ELEMENT 2 Sheets-Sheet l a fi Linden J Filed April 5. 1956 Feb.18, 1958 G. A. SAUNDERS 2,823,498

HONING ELEMENT 2 Sheets-Sheet 2 Filed April 5. 1956 5% l 7 2 b WC w v 5/s H 2 I m 5 O 9 a O wk 1. 2 2% m w z m m a 9 Z z 2 MVETIQTQM e tjuvnciem/f Gear W2 Maw HONING ELEMENT George A. Saunders, Rockford, Ill.,assignor to Barnes Drill Co., Rockford, Ill., a corporation of IllinoisApplication April 5, 1956, Serial No. 576,402 3 Claims. (Cl. 51-204 Thisinvention relates to a honing element comprising an abrasive stick and aholder therefor adapted to fit closely in the slot of a rotary body forradial shifting by. an expanding cam. The invention has more particularreference to the manner of frictionally holding the honing element inits slot. v

The general object is to provide between the honing element and theassociated cam follower a novel disengageable connection which permitsof low cost manufacture of the element, a wide range of adjustment andlong wear of the abrasive stick, ready replacement of the element whenworn, and solid backing of the stick during service use.

A more detailed object is to frictionally hold the cam follower plate inthe hone body and interlock with the plate the projecting ends of asimple holder secured to the bottom of thestick. H v

The invention also resides in the novel construction of the interlockingjoint which permits sidewise shifting of g the honing elementrelative tothe follower plate and into solid abutment with the trailing side wallof the body slot.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which Figure 1 is a fragmentary longitudinalsectional view of a honing tool having abrasive elements embodying thenovel features of the present invention.

Figs. 2 and 3 are fragmentary sections taken respectively along thelines 2-2 and 3-3 of Fig. 1.

Fig. 4 is an exploded perspective view of the improved honing elementand its support.

Fig. 5 is a fragmentary view of part of Fig. 1 showing another positionof the cam follower by which the honing element is expanded.

Fig. 6 is a section taken along the line 6-6 of Fig. 5.

Fig. 7 is a perspective view of a modified form of the honing element.

Fig. 8 is a perspective view of the modified abrasive stick holder.

Referring first to the form shown in Figs. 1 to 4, the improved honingelement is especially adapted for use in a rotary honing tool havingelongated parallel sided slots 10 angularly spaced around the tool body11 and each adapted to receive a composite replaceable honing element 12comprising an abrasive stick 13 and a holder 14 therefor. The stick isan elongated block of bonded abrasive covered on at least one side andin this instance on both sides with a thin strip 15 of resinous plasticmaterial which is adapted to wear down with the working face 16 inservice use. In this instance, the strips 15 extend from the workingface all the way down to the bottom of the stone. The combined width ofthe stone and the strips is only slightly less than the width of theslots 10.

The honing elements 12 are adapted to be expanded radially by the usualconical cams 17 spaced along a 2 push rod 18 slidable axially of thebody 11. The cam surfaces bear against complemental surfaces on thenarrowed inner edges of projections 19 spaced along the inner edge ofelongated follower plates 20 adapted to fit closely within the slots 10both laterally and longitudinally. Preferably and for a purpose toappear later, the

outer flat faces 21 of the plates 20 are disposed slightly beyond theouter periphery of the body 10 when the push rod 18 is in its limitposition shown in Fig. 5 of maximum expansion of the follower plates.

In accordance with one aspect of the invention, the

different radial positions of the follower plates 20 are maintainedfrictionally. This may be accomplished for example by plugs 22 of firmresiliently yieldable material such as rubber pressed into transverseholes 23 in the plates 20 and having a free length slightly greater thanthe Width of the plates so that at least one end 24 (see Fig. 4)projects a short distance, for example, of an inch, beyond the side ofthe plate before insertion thereof in a slot 10. By pressing the plugends inwardly, the bar with the plugs thereon may be inserted edgewisebetween the side walls of the slot, the follower projections 19 thusbecoming seated against the earns 17. With the plug thus compressed andabutting against the slot walls, enough friction will be created to holdthe plates .securely within the slots under the centrifugal forcesencountered in the service use of the tool. T he friction de- 19. Inthis location, the plug ends remain in engagement with the slot walls inall ofthe degrees of expansion 4 of the plates.

The invention contemplates the provision of a novel means for connectingthe honing element 12 detachably to oneof the plates 20 so that thefriction on theplates is also utilized to 'hold the elements in theslots while at the same time permitting lateral shifting of the elementrelative to its supporting plate into firm abutting contact with thetrailing wall of the slot as shown in Fig. 3. This connecting meansincludes the holder 14 which, in the form shown in Figs. 1 to 4,comprises a relatively thin and flat bar 25 of metal corresponding inwidth approximately to the stick 13 and its side coverings 15 but longerthan the stick so that the ends 26 of the bar extend beyond oppositeends of the stick. These ends, when the bar is lying against the outersurface 21 of the follower plate 20, project into squared notches .27formed in lugs 28 upstanding from the ends of the bar and having ends 29turned inwardly and toward each other so as to overlie the bar ends 26and hold the honing element against the follower bar. the bar 25 so thatby shifting the honing element laterally with the ends 26 in registerwith the notches, these ends will interlock with the lugs 28 as thehoning element is brought into the plane of the plate 20 as shown inFig. 3.

The lugs 28 may perform the additional function of holding the honingelement against endwise shifting during its reciprocation while engagingthe work. For this purpose, the ends 29 of the lugs may project close tothe ends of the abrasive stick or, as in this instance, be positionedfor engagement with short lugs 30 struck out of the holder ends 26 andupstanding at the ends of the stick in abutment with the latter.

To remove a worn out set of honing elements in a hone constructed asabove described, the push rod 18 and the cams thereon are shifted to thelimit position shown in Fig. 5 thus fully expanding the follower plates20 so as to expose their outer edges 21 above the periphery of the body11. The worn out honing elements may then he slid sidewise out of thenotches 27 and thus separated from the plates as shown in Fig. 6. Newhoning elements are then inserted and brought into edgewise alinementone Patented Feb. 18, 8

The notches 27 are open at the sides of corresponding plates 20, eachelement, after retraction of the expanding cams, may be pushed down intothe slots until the working faces 16 are spaced only a short distanceoutwardly beyond the periphery of the body. The tool is then ready forservice use, the folslower plates 20 being held frictionally in theslots by the plugs 22 and the honing elements being held by virtue ofthe interlocking of the bar ends 26 and the lugs 28. At the same time,each element is free to shift sidewise along the top 21 of its plate 20and thus come solidly against the trailing side wall-of the slot underthe circumferentially directed friction force applied to the workingface 16 of the element when this face first comes into contact with awork surface with the hone rotating. Thus, each honing element-s,although received loosely in its slot, is shifted automatically toworking position without the necessity of disturbing the accuratelyguided follower plates.

By making the bar wider than the bottom of the 7 stick 13 as shown inFig. 3 andextending the side strips 15 clear to the stick bottom, theexpanding pressure exerted by the cams is transmitted through the bardirectly to the strips rather than through the adhesive securing thestrips to the stick. The possibility of the strips being dislodged inservice use is thus avoided.

If desired, the nonmetallic coverings 15 at the sides of the stick 13and the holder 14 including the bar 25 for supporting the latter and forinterlocking with the lugs 28 may be formed as one unitary piece andtake the form of a channel as shown in Figs. 7 and 8. The lugs of theconstruction shown in Fig. 4 are omitted and the lug ends 29 areextended for abutment with the ends of the abrasive stick.

I claim as my invention:

1. For use in a hone having a rotary body and an elongated slot therein,the combination of, an elongated member adapted to fit loosely in saidslot, a resiliently yieldable member projecting from said member andfrictionally engageable under compression with a wall of said slot tohold the member in the slot during rotation of said body, lugs atopposite ends of said member upstanding from the outer facethereof andturned inwardly to form opposed notches open'in at least one directionlaterally of the member, a stickof bonded abrasive lying along said faceand disposed between said lugs, and a holder underlying -the.bottom ofsaid stick and rigidly secured to the latter, said "holder having endsprojecting beyond opposite ends of the stick and adapted to enter saidnotches by bodily edgewise movement of the holder.

2. For use in a hone having a camfollower plate with outstanding lugsnear opposite ends defining opposed notches facing toward each otheralong the outer edge of the plate, a honing element comprising a stickof bonded abrasive adapted to fitbetweensaid lugs,.a strip ofnonmetallic material covering at. least one side of said stick andextending to the bottom thereof, and a flat bar extending along andrigidly secured tothebottom of said stick with one edge underlyingandengaging the lower edge of said strip, the ends of said bar. projectingbeyond the ends of said stick and being adapted to. enter said notchesbybodily edgewisemovement of the bar while lying against said plate edge.

3. A homingelement as defined by claim 2 including projections rigidwith saidbar and. upstanding from the latter short of the bar ends. andadjacent opposite ends of said stick.

References Cited in the: file of thispatent UNITED STATES PATENTS1,698,590 Harter Jan. 8,1929 2,106,205; Connor Ian.- 25, 1938 2,201,593Prange May 21, 1940 2,265,377 Kline Dec. 9, 1941 2,751,726 Klein June26, 1956

